package com.proj.mhl.dao;


import com.proj.mhl.utils.JDBCUtilsByDruid;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import org.apache.commons.dbutils.handlers.ScalarHandler;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.List;

/*
* BasicDAo类
* 其他DAo的父类
* 用泛型指定具体类型
* */
public class BasicDAo<T> {//用泛型指定具体类型
    private QueryRunner qr = new QueryRunner();

    //DML通用的，针对任意表的增删改
    public int update(String sql,Object... parameters){
        Connection connection = null;
        try {
            connection = JDBCUtilsByDruid.getConnection();
            int update = qr.update(connection,sql,parameters);
            return update;
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }finally {
            JDBCUtilsByDruid.close(null,null,connection);
        }
    }

    //返回多个对象(即查询的结果是多行), 针对任意表

    /**
     *
     * @param sql sql 语句，可以有 ?
     * @param clazz 传入一个类的Class对象 比如 Actor.class
     * @param parameters 传入 ? 的具体的值，可以是多个
     * @return 根据Actor.class 返回对应的 ArrayList 集合
     */
    public List<T> queryMulti(String sql,Class<T> clazz,Object...parameters){
        Connection connection = null;
        try {
            connection = JDBCUtilsByDruid.getConnection();
            return  qr.query(connection,sql, new BeanListHandler<T>(clazz),parameters);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }finally {
            JDBCUtilsByDruid.close(null,null,connection);
        }
    }

    //查询单行结果 通用方法
    public T querySingle(String sql,Class<T> clazz,Object...parameters){
        Connection connection = null;
        try {
            connection = JDBCUtilsByDruid.getConnection();
            return  qr.query(connection,sql, new BeanHandler<T>(clazz),parameters);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }finally {
            JDBCUtilsByDruid.close(null,null,connection);
        }
    }

    //查询单值方法
    public Object queryScalar(String sql,Object parameters){
        Connection connection = null;
        try {
            connection = JDBCUtilsByDruid.getConnection();
            return  qr.query(connection,sql, new ScalarHandler(),parameters);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }finally {
            JDBCUtilsByDruid.close(null,null,connection);
        }
    }
}
